SFI SYSTEM(w/ EGR System) ECM Power Source Circuit

DTC Code DTC Name
ECM Power Source Circuit

DESCRIPTION

When the engine switch is turned on (IG), the battery voltage is applied to the IGSW terminal of the ECM. The output signal from the MREL terminal of the ECM causes a current to flow to the coil of the No. 1 integration relay (EFI relay), closing the contacts and supplying power to terminals +B and +B2 of the ECM.

WIRING DIAGRAM

A227243E09

CAUTION / NOTICE / HINT

Note:

Inspect the fuses for circuits related to this system before performing the following inspection procedure.

PROCEDURE

  1. CHECK NO. 1 INTEGRATION RELAY (POWER SOURCE)

    1. Remove the No. 1 integration relay from the engine room relay block.

    2. A223349C01

      *1

      Engine Room Relay Block

      *a

      Front view of wire harness connector

      (to No. 1 Integration Relay)

      Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection

      Condition

      Specified Condition

      1C-1 - Body ground

      Always

      11 to 14 V

      Result

      Result

      OK

      NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (NO. 1 INTEGRATION RELAY - BATTERY)

    OK

  2. INSPECT NO. 1 INTEGRATION RELAY (EFI)

    1. Inspect the No. 1 integration relay (EFI).

      Click here

      Result

      Result

      OK

      NG
    NG

    REPLACE NO. 1 INTEGRATION RELAY

    Click here

    OK

  3. CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - ECM, BODY GROUND)

    1. Check the harness and connectors between the No. 1 integration relay and ECM.

      1. Remove the No. 1 integration relay from the engine room relay block.

      2. Disconnect the ECM connector.

      3. Measure the resistance according to the value(s) in the table below.

        Standard Resistance

        Tester Connection

        Condition

        Specified Condition

        G44-9 (MREL) - 1B-2

        Always

        Below 1 Ω

        G44-22 (+B) - 1B-4

        Always

        Below 1 Ω

        G44-23 (+B2) - 1B-4

        Always

        Below 1 Ω

        G44-9 (MREL) or 1B-2 - Body ground

        Always

        10 kΩ or higher

        G44-22 (+B) or 1B-4 - Body ground

        Always

        10 kΩ or higher

        G44-23 (+B2) or 1B-4 - Body ground

        Always

        10 kΩ or higher

    2. Check the harness and connectors between the No. 1 integration relay and body ground.

      1. Measure the resistance according to the value(s) in the table below.

        Standard Resistance

        Tester Connection

        Condition

        Specified Condition

        1B-3 - Body ground

        Always

        Below 1 Ω

        Result

        Result

        OK

        NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK HARNESS AND CONNECTOR (ECM - BODY GROUND)

    1. Disconnect the ECM connector.

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      C30-12 (E1) - Body ground

      Always

      Below 1 Ω

      Result

      Result

      OK

      NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. INSPECT ECM (IGSW VOLTAGE)

    1. A223350C01

      *a

      Rear view of wire harness connector

      (to ECM)

      Disconnect the ECM connectors.

    2. Turn the engine switch on (IG).

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection

      Switch Condition

      Specified Condition

      G45-21 (IGSW) - C30-12 (E1)

      Engine switch on (IG)

      11 to 14 V

      Result

      Result

      OK

      NG
    OK

    REPLACE ECM

    Click here

    NG

  6. INSPECT NO. 1 INTEGRATION RELAY (IG2)

    1. Inspect the No. 1 integration relay (IG2).

      Click here

      Result

      Result

      OK

      NG
    NG

    REPLACE NO. 1 INTEGRATION RELAY

    Click here

    OK

  7. CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - ECM)

    1. Remove the No. 1 integration relay from the engine room relay block.

    2. Disconnect the ECM connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      1A-5 - G45-21 (IGSW)

      Always

      Below 1 Ω

      1A-5 or G45-21 (IGSW) - Body ground

      Always

      10 kΩ or higher

      Result

      Result

      Proceed to

      Out of normal range

      A

      Within normal range

      B
    A

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    B

  8. CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - POWER MANAGEMENT CONTROL ECU)

    1. Remove the No. 1 integration relay from the engine room relay block.

    2. Disconnect the power management control ECU connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      1A-1 - G38-8 (IG2D)

      Always

      Below 1 Ω

      1A-3 - Body ground

      Always

      Below 1 Ω

      G38-8 (IG2D) - Body ground

      Always

      10 kΩ or higher

      Result

      Result

      OK

      NG
    OK

    CHECK ENTRY AND START SYSTEM

    Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR